These investigations aimed to determine bio-insecticide effect of black cumin essential oil against granary weevil, Sitophilus granarius L. on stored wheat. Therefore three different experiments with black cumin were carried out: I. To test efficacy of black cumin against different developmental stages of granary weevil in soft wheat grain; II. To test effective concentration of black cumin against granary weevil in space 50% filled up with wheat applying black cumin in the concentration range of 25, 50, 100, 175 and 275 mg/ml; III. To test effective concentration of black cumin in spaces differently filled up with wheat (empty space, 50% and 95% filled up). Though black cumin exhibited certain fumigant characteristics it would be needed to apply high concentrations relative to phosphine or methyl bromide to gain satisfactory results. If the problem of cost-effective commercial production can be solved, black cumin could find a place in IPM strategies, especially where the emphasis is on environmental, food and human safety and on replacing the more dangerous and toxic fumigants and insecticides.